1. Field of the Invention
The present invention relates to electrically operated vehicles, particularly two-wheeled vehicles but including vehicles having more than two wheels, and specifically frame elements and a structural configuration for such vehicles.
2. Background Art
It is known in the art to provide multi-wheeled vehicles with electric motors for power and propulsion. Interest in electrically-powered vehicles, including but not limited to electrically powered motorcycles and scooters, is increasing due to the rising costs, and environmental impacts, of fossil-fuel-powered vehicles. Japanese patent reference JP 2004 210 072A discloses an electric motorcycle. This motorcycle has an electric drive motor, the output torque of which is shafted to the rear wheel of the motorcycle. An energy storage device in the form of batteries is arranged above the drive motor, i.e., spaced away from the drive unit including the electric drive motor.
Known from Japanese patent reference JP 05 065 085 A is an electrically powered motorcycle having an electric drive motor which transfers its output torque to the rear wheel via a drive chain. The electrical energy storage device, in the form of batteries, is disposed between two box-shaped frame profiles, that is, above the electric drive motor and spaced away there from.
Known from U.S. Pat. No. 5,501,292 B1 is an electrically operated motorcycle having a battery located between two lateral frame profiles, and connected to the steering head tube of the frame. The battery is arranged above the drive motor, spaced away there from. This patent seems also to disclose an embodiment, having batteries both above and below the drive motor, which communicates its drive energy via a drive train including a primary drive and a secondary drive to the rear wheel of the motorcycle. The primary drive in this arrangement is a CVT variator with which the translation ratio can be continually varied and featuring, at both the drive motor shaft and at the transmission input end, a pair of bevel gears which can be coupled into the torque transmission by means of a centrifugal clutch.
U.S. Pat. No. 5,657,830 A shows a generic vehicle arrangement with batteries provided to power the electric motor.
Known further from German Pat. No. DE 603 00 636 T2 is an electric vehicle having a battery assembly which can be defined on a saddle support of the vehicle. Serving as the drive motor is a drive assembly arranged in the rear wheel. The drive assembly is a wheel hub motor arranged physically separate from the battery assembly.
Known from German Patent Application No. DE 10 2007 019 803 A1 is a frame for a variable battery box characterized in that the battery box is disposed between frame tubes of the two-wheeler furnished therewith; further details regarding the arrangement of the battery box in relation to an electric motor appear to be lacking.
Known from international patent publication number WO 2005/044602 A2 is a frame structure of a two-wheeler with a battery tray which can be located between the frame struts.
Known further from German Pat. No. DE 42 01 207 A1 is an electrically powered two-wheeler featuring a battery box between two frame links, a drive motor being arranged separate from the battery box.
Electrically operated motorcycles as described above have an energy storage device which needs to be regularly recharged. For recharging, the energy storage device is connected to a charging device or the like, or, as an alternative, the discharged energy storage device can be removed from the vehicle and replaced by a freshly charged energy storage device or an energy storage device still having sufficient capacity.
With the known motorcycles as described hereinabove, an electric conducting connection needs to be unmade between the drive unit and the energy storage device. The connection may be in the form of a connecting cable; after the cable is disconnected, the discharged energy storage device is removed from the motorcycle. The removal process usually requires the application of a tool—which is likewise needed when the new energy storage device is fitted to the motorcycle, and the electric conducting connection between the drive unit and the energy storage device re-established.
Such connection-disconnection activity takes time and effort. Moreover, the existence of the electric conducting connection, typically in the form of a cable between the energy storage device and drive unit, also may constitute a safety and operating risk. Although a coded plug and socket unit provides polarization, any freely located or accessible electric wiring poses a risk of injury from the high voltages and currents that exist between the drive unit and the energy storage device on powerful motorcycles.
Also, when an electrically operated motorcycle is negotiating difficult terrain, the added possibility exists that the bike may topple, or one of its wheels lose grip in an unintended manner, causing damage to the electric cable connecting the drive unit and the energy storage device.
Furthermore, motorcycles as described have a complex configured drive train. To attain the desired driving power, the electric motor needs to achieve relatively high rotary speeds which have to be reduced in the primary drive of the drive train. For this purpose, a CVT transmission often is provided as the primary drive. Also known is to provide a chain drive, instead of a CVT transmission, as the primary drive. Both of these solutions have drawbacks because they occupy considerable space, especially in the longitudinal direction of the primary drive, due to the traction means often being in the form of a belt or chain. Additionally, this type of primary drive is a disadvantage for the dynamic performance of the vehicle fitted therewith, because longitudinal vibrations of the traction means may occur, thus consuming driving power in the primary drive. Moreover, these known systems may also cause a noise nuisance, and the extra compartment needed for the traction means also adds to the weight of the primary drive and thus of the vehicle as a whole; the latter being non-conducive to the wanted dynamic response of the vehicle.
With the foregoing as background, an object of the apparatus described hereinafter is to eliminate the described drawbacks by sophisticating the vehicle so that there are no longer exposed connecting leads between the energy storage device and the drive train. Also there is provided hereby an apparatus in which the drive train of the vehicle loses less energy than is the case with known, generic, electrically operated vehicles.